President Vladimir Putin welcomes President Barack Obama and the other heads of the world's leading and emerging nations to a G20 summit in St Petersburg today - an event crackling with tensions over the case for punitive strikes against Syria for allegedly using chemical weapons against its own people.
The stage was set for one of the most awkward and uncomfortable international summits in recent memory with the Syrian crisis likely to dominate discussions and the two heavyweights at the table facing off on the best way forward.
At a stop-over in Stockholm, Obama said the responsibility to act on Syria was not just his, but the whole world's. "I didn't set a red line. The world set a red line when governments representing 98 per cent of the world's population said the use of chemical weapons is abhorrent."
For his part, Putin said: "We have our ideas about what we will do and how we will do it in case the situation develops toward the use of force."
In Stockholm, Obama was speaking to several audiences at once - to Putin, to the other leaders at the summit, and to politicians in Washington whose support he needs. The US Congress is likely to vote on his request to launch military strikes next week.
